Why does my breaker trip when the AC starts?
The most common causes are an overloaded shared circuit, a breaker rated too low for the AC’s starting current, undersized or loose wiring, low supply voltage, or an earth leakage fault in the AC. A dedicated AC circuit with correctly sized cable and breaker solves most cases.
The 6 common causes
- Shared circuit: the AC shares a breaker with sockets, a fridge or an iron.
- Breaker too small: compressors draw a high current for a moment at start-up.
- Undersized cable: thin cable heats up and drops voltage.
- Loose or burnt connections: at the plug, socket or DB terminal.
- Low voltage: common on overloaded feeders in summer evenings.
- Earth leakage: moisture or a fault inside the AC trips the RCD.
What you can check safely
- Is the AC on its own breaker in the DB?
- Is the plug or socket warm, discoloured or melted?
- Does it trip only at a certain time of day (low voltage)?
What an electrician should do
Measure starting and running current, check voltage, inspect terminals, test insulation, and if needed install a dedicated circuit with the right cable and breaker, plus stabiliser or surge protection.
See AC installation and AC wiring in Lahore.
Frequently asked questions
Should I replace the breaker with a bigger one?
Not on its own. A bigger breaker on thin cable can let the cable overheat. Cable and breaker must be sized together.
Can low voltage damage my AC?
Yes. Persistent low voltage makes the compressor draw more current and run hot. A stabiliser or inverter AC with wide voltage range helps.
Fix AC tripping in Lahore
Call or WhatsApp with your problem and area. We confirm the visit time and visit charge before anyone comes.
